[cl-typesetting-devel] *use-exact-char-boxes*

[Marc Battyani]

"Dmitriy Ivanov" <divanov at aha.ru> wrote:

> "Marc Battyani" <marc.battyani at fractalconcept.com> wrote:
>
> |> I would like to use exact char boxes not only in math mode but also in
> |> other places. As I have noticed earlier, text would look prettier
> |> within table cells and draw-block. When *use-exact-char-boxes* is nil,
> |> the internal baseline of the first line in block is equal to dy and
> |> that leads to shifting the entire text down.
> |
> | Maybe the problem is here. Have you a simple example so that I can look
> | at it and see exactly what you mean?
>
> Here is the simplest example. You could see an unpleasant effect with
> padding equal to 0 and *leading-ratio* equal to 1.
>
> Within the first table, text in the bottom line breaches the border.
> Within
> the second one, the leading 1.0 is not actually respected.
>
> (defun test-char-mode (&optional (file (lw:current-pathname
> "char-mode.pdf")))
>  (tt:with-document ()
>    (let ((tt:*default-font* (pdf::get-font "Helvetica"))
>          (tt::*leading-ratio* 1.)
>          content)
>     (let ((tt::*use-exact-char-boxes* nil))
>       (setq content (tt:compile-text ()
>         (tt:paragraph (:top-margin 10 :h-align :center)
>           (tt:format-string "*leading-ratio*=~S *use-exact-char-boxes*=~S"
>                             tt::*leading-ratio*
> tt::*use-exact-char-boxes*))
>         (tt:table (:col-widths '(300 100) :border 1/2 :padding 0
> :cell-padding 0)
>           (tt:row ()
>             (tt:cell ()
>               (tt:with-style (:h-align :left :font-size 20)
>                 (dotimes (i 5)
>                   (tt:put-string "The cool Common Lisp typesetting system.
> "))))
>             (tt:cell () "test")))))
>       (tt:draw-pages content :margins #(30 30 30 30)))
>     (let ((tt::*use-exact-char-boxes* t))
>       (setq content (tt:compile-text ()
>         (tt:paragraph (:top-margin 10 :h-align :center)
>           (tt:format-string "*leading-ratio*=~S *use-exact-char-boxes*=~S"
>                             tt::*leading-ratio*
> tt::*use-exact-char-boxes*))
>         (tt:table (:col-widths '(300 100) :border 1/2 :padding 0
> :cell-padding 0)
>           (tt:row ()
>             (tt:cell ()
>               (tt:with-style (:h-align :left :font-size 20)
>                 (dotimes (i 5)
>                   (tt:put-string "The cool Common Lisp typesetting system.
> "))))
>             (tt:cell () "test")))))
>       (tt:draw-pages content :margins #(30 30 30 30) :break :after))
>     (pdf:write-document file))))
>
> (test-char-mode)

OK looks like the descent is not taken into account in the first case and it
should be fixed but, as I already wrote, using exact-char-boxes will lead to
non uniform line spacing. See your example modified: (pdf attached)

(defun test-char-mode (&optional (file #P"/char-mode.pdf"))
  (tt:with-document ()
    (let ((tt::*default-font* (pdf::get-font "Helvetica"))
          (tt::*leading-ratio* 1.)
          content)
     (let ((tt::*use-exact-char-boxes* nil))
       (setq content (tt:compile-text ()
         (tt:paragraph (:top-margin 10 :h-align :center)
           (tt:format-string "*leading-ratio*=~S *use-exact-char-boxes*=~S"
                             tt::*leading-ratio*
tt::*use-exact-char-boxes*))
         (tt:table (:col-widths '(300 100) :border 1/2 :padding 0
:cell-padding 0)
           (tt:row ()
             (tt:cell ()
               (tt:with-style (:h-align :left :font-size 20)
                 (tt:put-string "Apa Apaaa Apaaaa Apaaa Apaaaa Apaaa Apaaa
Apaaa")
                 (tt:put-string "aaa aaaaa aaaaaa aaaaaa aaaaaa aaaaaa
aaaaaa aaaaa aaaa aaaaa aaaaa ")
                 (dotimes (i 4)
                   (tt:put-string "The cool Common Lisp typesetting system.
"))))
             (tt:cell () "test")))))
       (tt:draw-pages content :margins #(30 30 30 30)))
     (let ((tt::*use-exact-char-boxes* t))
       (setq content (tt:compile-text ()
         (tt:paragraph (:top-margin 10 :h-align :center)
           (tt:format-string "*leading-ratio*=~S *use-exact-char-boxes*=~S"
                             tt::*leading-ratio*
tt::*use-exact-char-boxes*))
         (tt:table (:col-widths '(300 100) :border 1/2 :padding 0
:cell-padding 0)
           (tt:row ()
             (tt:cell ()
               (tt:with-style (:h-align :left :font-size 20)
                 (tt:put-string "Apa Apaaa Apaaaa Apaaa Apaaaa Apaaa Apaaa
Apaaa")
                 (tt:put-string "aaa aaaaa aaaaaa aaaaaa aaaaaa aaaaaa
aaaaaa aaaaa aaaa aaaaa aaaaa ")
                 (dotimes (i 5)
                   (tt:put-string "The cool Common Lisp typesetting system.
"))))
             (tt:cell () "test")))))
       (tt:draw-pages content :margins #(30 30 30 30) :break :after))
     (pdf:write-document file))))

Marc